I created a project called MeshWatch (originally MeshTalk, but that name was already in use). I use this tool to decode the messages being sent amongst the devices in my mesh. Packets are decoded and displayed in real time. There is a test function as well that will send out X messages every Y seconds. This is useful when moving devices around to see if they can still communicate. Each node in the mesh can be displayed along with their distance from the base (the node MeshWatch is attached to).
Feature suggestions are more than welcom.